1. Field of the Invention.
This invention has relation to snow removal apparatus wherein snow is removed from the ground, delivered into a snow reduction chamber where it is reduced to liquid water, and the liquid water is discharged into an appropriate sewer-like receptacle.
2. Description of the Prior Art.
It has been recognized for many years that a logical way to remove snow from streets and highways is by converting it into liquid water; and for that reason, many devices have been evolved to melt snow for disposal. See, for example, the following U.S. patents.
U.S. Pat. No. 3,304,632 to Kotlar et al. in Feb. 1967; PA1 U.S. Pat. No. 3,309,798 to Devlin et al. in Mar. 1967; PA1 U.S. Pat. No. 3,452,459 to Campion in July 1969; PA1 U.S. Pat. No. 3,464,128 to Krickovich in Sept. 1979; and PA1 U.S. Pat. No. 4,353,176 to Hess in Oct. 1982.
The patent to Campion discloses the use of a high volume of air flow to draw air from the ambient temperature to entrain water vapor and moisture from melted and melting snow and to carry this air-entrained water vapor back into the outside atmosphere. FIG. 1 discloses the discharge of snow from a snowblower into a snow reduction chamber equipped with a plurality of spaced-apart Calrod units throughout the chamber. It also discloses, in FIG. 5, the discharge of snow through the top of a snow reduction chamber into open ended and perforated tubes which are discharging the products of combustion into the chamber, with the discharge of water vapor coming out of the top of the snow reduction chamber. Campion appears to depend on the low humidity of cold ambient outside air to pick up the moisture laden air inside of his snow reduction chamber and to depend on an enormous air flow with the resulting dissipation of an enormous amount of heat energy to accomplish this transfer. It is suggested that the moisture laden air discharged from his apparatus will substantially instantaneously lose its moisture in the form of new falling snow.
The patent to Kotlar et al. discloses the use of high pressure/velocity air supplied to an oil burner to provide a flow of combustion products and air into which is entrained snow to be reduced, the snow presumably being carried to the end of a snow melting chamber 40 where the liquid water drops through into an otherwise unheated water tank 60 while the combustion products and any remaining air passes out through exhaust stack 49. This system appears to involve the discharge of immense amounts of heat energy into the ambient atmosphere; and would appear to be quite susceptible to clogging or choking when subjected to the introduction of very large amounts of snow or snow which is full of ice. See the patent to Devlin, column 1, sentence beginning on line 24.
The patent to Devlin et al. deposits the snow inside of its snow reduction chamber onto an auger and moves it through a perforated tube as a slurry. While moving through the tube, water in a tank at the bottom of the snow reduction chamber is heated in a boiler and is introduced into the snow moving through the perforated cylinder to be discharged at the open end thereof into the tank. A substantial quantity of heat energy must be injected into the water initially in the tank before the Devlin apparatus is ready to receive snow. Also, although provision is made so that any large rocks discharge from the open end of the auger cylinder are separated from the other liquid water, the gravel, dirt, roadside and street trash and the like which are inevitably picked up in any snow removal process are all co-mingled with the heated circulated water and will, it is respectfully contended, inevitably serve to clog up the boiler tubes when they are part of the water being circulated.
The patent to Hess relies on a combustion burner which produces combustion gases which are forced up through pipes encircling the outside of a rounded V-shape container and down into the snow which is collected in this container. An auger in the bottom of the container agitates the slurry of solid water (snow and ice) and liquid water and tends to carry it toward the rear lower portion of the rounded V-shape container where the water flows up around the V-shape container until it is drained away through an exit port. It appears as though all of the heat energy put into the snow reduction process, and any that is not utilized in the process, is discharged along with the liquid water, and not recirculated.
The patent to Krickovich discloses what is the equivalent of a large stew pot into which snow is loaded, the pot being stirred by spokes of agitators 56 and 64, and the pot being heated using a series of gas burners 68 not unlike gas burners used to heat a stew pot in a kitchen. Evidently the snow first discharged into this pot, if the pot is preheated, will tend to flash over into vapor and/or immediately melt. When sufficient snow has built up so that the paddles of the agitator 56 are moving the snow, the snow and liquid water are present in the form of a slurry.
What was needed before the present invention was a snow removal apparatus having a snow reduction chamber so designed that individual molecules of frozen water (snow and ice) can be brought in contact with a surface having a temperature above the melting point so that the conversion of the individual molecules from frozen to liquid state can be accomplished substantially instantaneously to prevent snow buildup in the chamber and resultant clogging or choking of the chamber.
Also needed was a means for having sufficient heat energy in all surfaces actually contacted by the snow and ice so that instantaneous melting will occur in those molecules actually touching the surface and by adjacent molecules by conduction; with the excess of heat energy being retained and not discharged with the liquid water or into the atmosphere.